Toss the tomatoes, garlic, onion, with oil on a foil lined baking sheet. Season well with salt and pepper. Broil until the tomatoes soften and the garlic and onion turn golden brown. Stir around the contents to allow them to get even coloring. Then remove from the oven and into a pot on medium heat.
Add the broth, cream, tomato paste, thyme, and sage. Bring to a simmer for about 5 minutes. Season with salt and pepper to taste. Stir to incorporate everything together. Remove from the heat. Remove the thyme sprigs.